Finding the Fourth Proportional to 2,186.88, 3,017.91 and 1,290.83

Step by Step Solution

1. Step 1: Write the proportion equation
   2,186.88 : 3,017.91 = 1,290.83 : x
2. Step 2: Convert to fraction form
   2,186.88/3,017.91 = 1,290.83/x
3. Step 3: Cross multiply
   2,186.88x = 3,017.91 × 1,290.83
4. Step 4: Simplify right side
   2,186.88x = 3,895,593.68
5. Step 5: Solve for x
   x = 3,895,593.68/2,186.88
6. Step 6: Final answer
   x = 1,781.35